What it means
Alarm A03506 reports that the 24 V power supply feeding the digital outputs on terminal X124 is missing. The manuals for G130, G150, S120 and S150 describe the message identically. The same condition can also be raised as a fault or as a message without a reaction — the drive's configuration decides which form appears.
Why it appears
- The 24 V supply for the digital outputs at terminal X124 is not present.
What to check
Check the terminals for the power supply voltage (X124, L1+, M).
Terminals L1+ and M are where the 24 V for the digital outputs is fed in; without it the drive raises this message.
Acknowledging and restarting
As an alarm, A03506 needs no acknowledgement. If the drive reports the same condition as a fault, it is acknowledged immediately via POWER ON.
The same on every family
Every manual that describes A03506 gives it the same reaction, acknowledgement and message class.
| Drive family | Reaction | Acknowledge | Message class | Component | Manual |
|---|---|---|---|---|---|
| S120, S150 | NONE | NONE | Supply voltage fault (undervoltage) (3) | None | SINAMICS S120, S150 List Manual · p. 2741 |
| G130, G150 | NONE | NONE | Supply voltage fault (undervoltage) (3) | None | SINAMICS G130, G150 List Manual · p. 1515 |
The drives this code lives on
A03506 is described for G130, G150, S120, S150. These are the converters of those families in our catalogue — price on request.
Questions technicians ask
What does alarm A03506 on a SINAMICS drive mean?
It reports that the 24 V power supply for the digital outputs on terminal X124 is missing. The message is described for G130, G150, S120 and S150.
How do I clear A03506?
Check the power supply voltage at terminals X124, L1+ and M. The alarm itself needs no acknowledgement; if the drive raises the condition as a fault, it is acknowledged immediately via POWER ON.
Can A03506 also appear as a fault?
Yes. The manuals list the same condition also as a fault and as a message without reaction, and the drive's configuration decides which form appears.
Codes next to this one
Source
Written from Siemens' own List Manuals and operating instructions; every number, designation and parameter on this page is checked against them before publication.
All SINAMICS codes: fault and alarm codes · the A03xxx group · SINAMICS manuals · Siemens manuals